Each wall keeps its own thickness
Exterior walls are drawn two or three times thicker than partitions, and recognition keeps that. Every wall lands where it is drawn and gets the thickness measured from the image: on our test plan of a new-build flat partitions came out at 9 cm and outer walls at 27 to 35 cm. Shared walls meet on one line without a gap, and furniture keeps clear of each wall by that wall's own thickness.
Doors by their arc, windows by their mullion
A gap in a wall says nothing on its own, so the drawing symbol decides. Doors have a swing arc from the hinge, windows a mullion line across the opening. Doors drawn half-open at 25 to 30 degrees still count. A gap that leads nowhere, usually the outline of a bathtub, is dropped.
A whole floor splits into flats
Upload a full floor and flats are separated by wall thickness: walls between flats are 43 to 54 cm on our test plan, partitions 13 to 15. Kitchens, bathrooms, balconies and corridors are then typed by area, shape and neighbours. On a 39-room test floor that found all six flats, kitchens and balconies.
Scale comes from the printed areas
Most plans print each room's area. The AI button numbers the rooms on the image and the model reads the figures, so 18.4 m2 on paper becomes 18.4 m2 in the scene. It takes 15 seconds to two minutes and needs the Repair plan or above; without it you set the scale by typing the total area.
Tricky plans can be traced
Skewed photos and hand sketches are recognised less reliably. In that case, place the picture under the plan as an underlay and trace the rooms corner by corner. Points snap to the lines of the drawing, and the scale is set with one segment of known length, such as an 80 cm doorway.